1. Field of the Invention
This invention relates to an optical apparatus for obtaining an image used by a user.
2. Description of Related Art
In the optical apparatus of this type, there has been the need that a user wants to observe in detail or magnify only a particular part of an image of an object should be observed in detail or magnified. In response to this, for example, in an imaging apparatus such as a digital camera or a TV camera, optical zoom or electronic zoom (also called digital zoom) has been used as the technique meeting the above need. The technique of the electronic zoom is set forth, for example, in Japanese Patent Kokai No. 2002-320135.
In a telescope, the magnification of an optical system has been changed by the replacement of an eyepiece to thereby meet the above need. In a microscope, an objective lens has been replaced to thereby satisfy the above need.
An optical apparatus using the electronic zoom, for example, the digital camera, is designed so that an image photographed and stored through an imaging optical system at the center of the imaging surface of an image sensor inside the digital camera is magnified by an image processor and is processed with respect to pixel interpolation. The image is thus displayed or output to a display device.
In the telescope or the microscope, when the eyepiece or the objective lens is replaced, combined aberration of the entire optical system is changed.